ensure 4-byte alignment for storage, as SkWriterBuffer requires it

tests/ImageIsOpaqueTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkTypes.h"
 #include "Test.h"
 
 #if SK_SUPPORT_GPU
 #include "GrContextFactory.h"
 #endif
 #include "SkImage.h"
 #include "SkSurface.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 
 static void test_flatten(skiatest::Reporter* reporter, const SkImageInfo& info) {
-    // just need a safe amount of storage
-    char storage[sizeof(SkImageInfo)*2];
+    // just need a safe amount of storage, but ensure that it is 4-byte aligned.
+    int32_t storage[(sizeof(SkImageInfo)*2) / sizeof(int32_t)];
     SkWriteBuffer wb(storage, sizeof(storage));
     info.flatten(wb);
     SkASSERT(wb.bytesWritten() < sizeof(storage));
 
     SkReadBuffer rb(storage, wb.bytesWritten());
     SkImageInfo info2;
 
     // pick a noisy byte pattern, so we ensure that unflatten sets all of our fields
     memset(&info2, 0xB8, sizeof(info2));
 
@@ skipping 54 matching lines @@
         SkImageInfo infoOpaque = SkImageInfo::MakeN32(5, 5, kOpaque_SkAlphaType);
         SkAutoTUnref<SkSurface> surfaceOpaque(SkSurface::NewRenderTarget(context, infoOpaque));
 #if 0
         // this is failing right now : TODO fix me
         check_isopaque(reporter, surfaceOpaque, true);
 #endif
     }
 }
 
 #endif